SEVERN TOWNSHIP, Ont. - Provincial police say a 21-year-old Victoria Harbour, Ont., man is dead following a collision in the southbound lanes of Highway 400 in Severn Township.

Police say Jonathan Antler-Paquette died in a multi-vehicle crash early Monday morning that closed the southbound 400 for several hours.

Investigators say after the driver of a southbound van lost control, struck a snowbank and flipped over, a motorist stopped to help.

Police say a truck driver was attempting to stop when the trailer jackknifed and struck and killed the motorist who stopped to assist.

The truck and trailer were across the highway when the fourth motorist ran into it.

The driver of the van was transported to hospital and has since been released. The two other drivers were not injured.